Sealing closure and method and apparatus for forming same



Feb. 25, 1964 F. M. HAGMANN E-rAL 3,122,252

SEALING CLOSURE AND METHOD AND APPARATUS FOR FORMING SAME Filed Oct. 5, 1959 3 Sheets-Sheet 1 2i; f, 21 if if 30 4 2 l s if Za ,//y//ll 26- if 5a l ML 49 Feb. 2`5, 1964 F. M. HAGMANN ETAL 3,122,262

y SEALING CLG-SURE AND METHOD AND APPARATUS FOR FORMING SAME l Filed oct. 5, 1959 s sheets-sheet 2 o je?.

Feb. 25, 1964 F M, HAGMA'NN ETAL 3,122,262

SEALING CLOSURE AND METHOD AND APPARATUS FOR FORMING SAME 3 Sheets-Sheet 3 Filed Oct. 5, 1959 YIO United States Patent Oli ice lZZh Patented Feb. 25, 1964 3,l22,22 SE. LNG CLGSUllE ANB METHD APPARATUS FR WGBH/ENG SAME Foster M. Hagmann, will 3rd Sit, Monica, Salif.; Hazen B. Graham, 746 Cory Drive, l .glen/ood 3, Calif.; and Robert B. vi'orr's, Zilel Quedo Drive, Woodland Hls, Calit.; said Graham and said Morris assignors oi' foul-tee and two-thirds percent to sai. l-lagrnann, and fourteen percent to W anda L. Pratt, Santa Monica, Calif.

Fil-ed Get. 5, 1959, Ser. No. 344,402 9 Claims. (El. 22d-4in) This invention relates generally to sealing devices and more particularly to a self-sealing closure which can be economically manufactured for use on disposable containers.

Tiere are in use a wide variety of sealing closures for bottles, jars, cans and the like which are provided with cork, cardboard, rubber or other forms of gasleting material. Such seals are of limited utility, both from a standpoint of irntial hermetic or vacuum sealing and from a standpoint of reusability. These factors limit the shelflife of the product and also the period of use of the product since the container cannot be erlectively resealed once it has been opened.

v-Vhile the disadvantages of conventional sealing closures have long been known, other types of seals have not been developed because the cost of a precision titted seal having an eiective sealing design has been too great for use in massproduced disposable containers. Also, because a low removal torque is desirable for the consumer, seal designers have attempted to seal with relatively low sealing or Contact pressures in screw-type closures.

G-ring type seals are well known for sealing use in precision equipment and have many advantages. They will seal effectively under light sealing pressures, and will seal against either a high iluid pressure or a vacuum. ln addition they are fully reusable, concontaminating and impervious to most all chemicals and substances. idowever, eiective O-ring sealing is dependent upon correct volumetric relationship between the O-ring and the groove or corr ling void space and requires close tolerance lits,

recision machining work, closely controlled inspection and testing, and other manufacturing techniques which are inherently expensive. Moreover, a loose G-ring, as is provi-ded by conventional O-ring and groove relationships, is not desirable in a container closure. For these reasons has not heretofore been thought that G-ring sealing could be successfully used in low cost container closures.

With the foregoing in mind it is a major object of this invention to provide a sealing closure which will seal errectively under all conditions, is fully reusable,

may be economically massproduced.

An equally important object of the invention is to provide a method and apparatus for for ng such seals wherein the rigid retaining body of the closure is formed and sized relative to a mating deformable sealing ring s that the correct void-volume relationship between ring and confining groove is maintained under adverse tolerance conditions.

A further object or the invention is to provide a sealing closure having a retained O-ring therein, and which because of the closely held volume-void relationship between ring and closure body may utilize a split ring formed as a low cost extrusion.

Another object of the invention is to provide methods and apparatus for forming and shaping a closure body around the bach portion of the sealing ring and utilizing the ring as a sizing element to control the shaping and amount of the body.

lt is also an object of the invention to provide a sealing closure which may be adapted to various types of container closure or caps, and which undergoes suilcient physical deformation upon sealing engagement to overcome surface irregularities in the opposed container face without danger of leakage.

Still another object of the invention is to provide a sealing closure having a small area of sealing contact whereby installation torques and clamping forces may be held to relatively low values for ease of consumer removal.

These and other objects and advantages of my inven- 'ou will become apparent from the following detailed den oi a preferred embodiment thereof and of apparatus for forming the device, and from an inspection of the accompanying drawings in which:

FEGURE l is an elevational view partially in section showing a preferred embodiment of the sealing closure installed on a typical container;

FlG. 2 is an enlarged sectional detail illustrating the relationship of the closure with the lip or face of the container prior to sealing engagement;

FlG. 3 is a cross-sectional view of one form of die stamping apparatus used in shaping the closure body to the sealing ring;

4 through 8 are a series of enlarged sectional etails illustrating the sequential steps in the final shaping of the retainer body to the sealing ring using the apparatus of FIG. 3;

llG. 9 is a cross-sectional View of an alternate form of die stamping apparatus used in shaping the closure body to th sealing ring;

IGS. l through i4 are a series of enlarged sectional details illustrating the sequential steps in the final shapof the retainer body to the sealing ring using the apparatus ot FlG. 9; and

FlG. 15 is a perspective view of the split sealing ring which may be used in the closure.

Referring now to the drawings and particularly to FlG. l thereof, the numeral 2l? designates a container which, in this instance, corn rises a glass jar or bottle having an upwardly open neck portion 2l that is terminated by an upwardly facing lip or face 22. The closure for container 2t), which herein illustrates the subject invention, has the form of a metallic cap 25 that is adapted for threaded engagement with the container by means of a female thread 2o, which engages with a complemental thread or rib 27 formed on the container in a conventional manner. It is to be understood, of course, that the container and closure which herein illustrate the invention may be of many different types without affecting the principles of operation of the invention.

Closure 2S is formed with a circular central body portion 23 having an integral downturned flange 29 thereon which carries the thread 26. At the outer edge of the circular body portion Z3, there is formed an annular recessed groove or channel 3@ that opens downwardly and is positioned directly above the container lip 22. As is best seen in FlG. 2, groove 3d is adapted to contain an annular sealing ring 3l having a downwardly projecting portion 32 which lies below the central portion of the cap 28, and also below a short out-turned shoulder 33 which joins the downturned flange 2.9 with the wall of groove 30. When the closure is moved from the position as shown in FlG. 2 to the tightened position of FlG. 1, it will 'oe understood generally that the ring 3l makes sealing contact with lip 22, and that the lower portion of the ring 32 is deformed upwardly to take the generally rectangular cross-sectional coniiguration shown in FIG. l. The body of closure 25 is herein illustrated as being formed of thin sheetrnetal, which is normally rigid so as to form a retainer for the ring 3l and is at the same time capable of being worked or shaped under die-stamping operations without fracturing or splitting. Some plastic materials have generally similar properties, and can be utilized in place of a metallic body. The ring 31 is formed as a resilient deformable member and may be made of either rubber or plastic compounds suitable for the enviroment of use.

Before considering the formation of closure in detail, it is pointed out that the ring 31 is made of a substantially incompressible material and that the volume of the ring is not changed by the deformation of shape which occurs upon sealing engagement. To achieve good sealing contact and at the same time prevent cold iiow or extrusion of the ring 31, it is therefore necessary to maintain a definite relationship between the volume of the ring 31 and the volume of the groove 3i). This relationship, herein referred to as the void-volume relationship, must be such that when the ring 31 is deformed from the physical shape shown in FIG. 2 to that shown in FiG. l, it is capable of iitting within the void space of the groove delined above the plane established by the lower face of the central body portion 28 and the outer shoulder 33. Since these face surfaces 23 and 33 establish a metallic stop which limits further tightening of the closure on the container, it will be understood that the desired sealing engagement is fully established when these surfaces abut upon lip 22. At this time the ring 31 must be confined entirely within groove 39, or else it will have cold-iiowed or extruded so as to have permanently deformed the ring preventing reuse of the seal and establishing leakage paths which destroy the sealing ability of the device. On the other hand, it can be seen that if the groove 3i) were to be substantially larger than the volume of ring 3i, the latter would not necessarily physically deform so as to undergo the substantial change in shape reilected between FIG. 2 and FIG. 1, and the resilient sealing contact or pressure of the sealing ring of the container lip 22 would not necessarily be achieved. For these reasons, the correct void-volume relationship between the ring 3i and the groove 30 is one in which the volume of the ring is only slightly less but in no event larger than the volume of the void space provided within the groove.

Considered from a practical manufacturing standpoint, it will be understood that the dimensions and shape of the ring 31 can only be controlled within a certain tolerance range. Likewise, certain tolerances exist on the dimensions of the groove 39 and these tolerances may combine to create an adverse tolerance condition in so far as the void-volume relationship is concerned. Therefore, to avoid holding these tolerances within extremely close limits, the closure of the present invention is iinally shaped by an apparatus and method which, in eiect, sizes the groove 30 to a particular sealing ring 31 which is thereafter to remain the permanent sealing ring for that complete sealing device. In this manner, the cost of the complete closure can be held within reasonably economical limits, and at the same time a precision void-volume relationship can be achieved.

Also, by closely controlling the void-volume relationship, it is possible to utilize a sealing ring 3l which is made in a split form as is illustrated in FIG. 15. As is therein seen, the ends of the ring 31 designated as 31A and 31B are merely brought together in abutting relationship and are held tightly against each other upon sealing deformation of the ring by the internal forces created within the ring due to its deformation. Since a positive seal must be created across ends 31A and 31B to prevent a leakage path, it can be understood that close control of the void volume relationship will ensure the necessary engagement between ends. From a cost standpoint, the ring 3l formed with split ends is considerably more economical than a ring which is molded in endless form since it may be merely formed as an extruded strip, cut to proper lengths.

One method of forming the closure so as to closely control the void-volume relationship will be described in connection with the apparatus shown in FIG. 3 and further explained by the sequential details FIGS. 4 through 8. The body of closure 25 is formed as a blank or stamping which initially has the shape as is shown in FIGS. 3 and 4 wherein it is in inverted position. The walls forming the groove 30 comprise inner and outer parallel side walls 35 and 35 respectively, and a iiat rear wall 37. These walls are, of course, all of annular conguration and the inner side wall 35 joins integrally with the central closure portion 2S while the outer side wall 36 joins integrally with the shoulder 33.

At this time, the separately formed ring 31 is tted in the groove 3i) and, as shown, this ring is originally of torus shape having a circular cross-section with a diameter substantially equal to the width of the groove and a volume which is purposely made greater than the volume of the groove defined below the plane established by the upper faces (FIGS. 3 through 8) ofthe portions 28 and 33. The geometry causes a substantial portion of the ring 31 to project upwardly and c-ut of the groove as is illustrated.

It will be remembered that the diameter of the ring 31 can only be established within a range of manufacturing tolerances, and that the width and depth of the groove 3i? can likewise only be established within a range of manufacturing tolerances. For these reasons, given any particular ring and separately formed closure body, there would be a considerable variation in the void-volume relationship of groove and ring as compared to the voidvolume relationship of other rings and bodies within manufacturing lots. For example, in one case the ring may be over-size and the groove under-size, while in another case the relationship may be vice versa.

In order to closely control the final void-volume relationship, the body of closure 25 utilizing the present invention is shaped or worked so that it is necessarily sized to the particular ring 3l which has been fitted therein. This may be done by the apparatus shown in FIG. 3, in which upper and lower die-stamping parts adapted for mounting in a conventional stamping press are illustrated.V A xed base plate 44B supports a lower die block 4lV which carries a circular upper boss 42 that is shaped to fit the central body portion 2S when the closure is seated thereon in inverted position. It should be noted that the depth or height of boss 42 is greater than the depth of side groove walls 35 and 36 so that the bottom groove wall 3'7 is not fixedly supported on the die block 41, but is spaced upwardly therefrom. Mounted above the block il is an annular member 43 which iits around the closure f flange 29 and holds it against outward movement. Between the block il and the member 43 are a pair of holding and forming plates 45 which are of split annular shape and are mounted for inward and outward sliding movement. These plates 45 are normally spring-urged outwardly by spring 46 secured to posts 47 carried by base plate 4i?. The inner faces of the plates 45 are beveled downwardly and outwardly at a small angle from the perpendicular to form inclined surfaces 48, and the outer faces of the plates are beveled inwardly and upwardly along surfaces 49. When seated on block 41, the closure 25 is positioned with the outer groove wall 36 opposed to the inner plate surfaces 48.

The upper die-stamping parts are all supported from a top plunger 52 which is mounted for vertical reciprocating movement in the press. Mounted on the bottom of plunger 52 is an outer skirt member 53, which is formed with a skirt thereon having a beveled lower edge 54 that is adapted to seat downwardly on the outer edges 49 of the plates d5. The angles on edges 49 and 54 as shown are each at 45 with the perpendicular but this relationship may be varied to give more or less driving action to the plates 45. Member 53 is held in spaced relationship to plunger 52 by springs 55 which are complementally seated Y therein. When the skirt member 53 seats downwardly on plates 45, the plates are driven inwardly and the inner inclined edges 4S of the plates seat against the outer groove wall 36, as illustrated in FIG. 5, with only the top corners of these surfaces 4S in actual seating engagement with the perpendicular groove wall 36.

Mounted concentrically Within the member 53 are three members which are adapted to t downwardly within the ange 29 of the closure body to exert forming pressure on both the body of the closure and the sealing ring. These members comprise a central cylindrical holding block which is held in spaced relationship to plunger 52 by spring 57, an intermediate annular forming sleeve or punch 53, and an outer annular forming sleeve 59. Outer forming sleeve 59 is also held in spaced relationship to plunger 52 by springs eil, but it should be noted that intermediate sleeve 53 is rigidly mounted on the bottom o the plunger 52 for positive driving action.

rl`he shape of the bottom edges of the members 555, 53 and 59 is of signiiicance, and the detail thereof can best be seen from an inspection of FIG. 8 wherein it will be noted that the bottom of intermediate sleeve S3 is at, is of a width just less than the width of the mouth of groove Sil, and that it normally lies recessed above the members 56 and 5?. A rounded downturned lip or knife edge 62 is formed on the outer edge of the central block 56 and a similar opposed lip 63 is formed on the inner edge of the outer sleeve 59. These lips 62 and e3 are shaped to set tightly against the radiused corners of the groove walls 35 and As the plunger 52 makes a downward stroke, the men-- bers S6, 53 and 59 all move downwardly together until member 56 seats on closure portion Z8 and member 59 seats on shoulder 33. This seating action iirmly holds the body of the closure in place, and edges 62 and 63 are seated against the upper corners of the groove walls as a further clamp. At the same time, the plates le' have moved inwardly, so that surfaces di; support the upper corner of the groove wall .3o. The downward movement of member 53 and its engagement with plates 45 actually occur simultaneously with the engagement of members Se and S9 on the closure body. ln the illustration of FlG. 5, only the action of member 53 was illustrated for clarity. At this point, the lower face or sleeve S8 has just seated against the upper rounded portion of the ring 3l, and as is illustrated in FlG. 6, contact has just been made and the upper rounded top of ring 3l has been slightly deformed towards a rectangular shape.

Upon further downward movement of plunger 52, the members 5h and 59 rem in their seated position as do the plates l5 under the action oi member 53. Buring this further movement, the upper springs S5, 57 and di? yield to allow the further downward movement of the plunger 52 and ot the fixed forming sleeve 53.

As sleeve 5S continues downwardly, it completely fiattens ring 3l into a rectangular shape and since the latter is incompressible, it thereafter acts as a hydraulic forming mediurn to transmit the applied load to the groove walls 35, 36 and 37. When the sleeve 58 is at the bottom of its stroke, it reaches the position shown in FIG. 7, and in so doing has worked or cupped the groove walls 35 and 36 downwardly to allow the groove to accommodate the total volume of the ring 3l therein. At the same time, it will be noted that the outer wall 36 has been angled outwardly toward the bottom and in a direction towards making Contact with the inclined plate edges 48.

The space as illustrated, which remains between the groove wall 36 and the inclined plate edge 43, may be termed a tolerance volume, and the parts are so designed that the wall 36 will not be inclined outwardly as much as the edge i8 unless the ring 3l has the largest possible volume within its tolerance range. ln thus shaping the groove wls to just t the ring 3l, it will be appreciated that the desired close control of the void-volume relationship has been achieved regardless of the initial tolerances in the diameter of the ring. As is seen in FIG. 7 the formation of the groove walls and the sizing of the 5 groove to the sealing ring 3l has been done with reference to the plane established by the upper surface of closure body portion 28 and 33. Since these are the same surfaces which limit the seating of the closure on the container in the use of the device, the usage conditions have been accurately simulated in the forming operation.

lt will also be noted, that since the wall 36 now closes inwardly towards the mouth of the groove, it acts to frictionally coniine the ring 3l within the groove and thus prevent separation of the parts. After the forming operation has been completed, as is illustrated in FIG. 8, the upper rounded portion of ring 3l, due to its inherent resilience and memory factor, will tend to return to its Outward rounded or arcuate shape. Thus, it will be in a position to make sealing engagement with the lip of the container upon installation of the closure as has previously been described.

ln FGS. 9 through 14 a somewhat different apparatus and method for forming the sealing closure is illustrated. This alternate forming apparatus also uses die forming but applies the forming pressure to the back or outside surface of the closure body, and utilizes a body blank or stamping which has a different shape in its preformed state. The starting shape of the closure body is best seen from an inspection or" FIGS. 9 and l0. For clarity, portions of the body which have the same shape as those previously described have been given the same reference numerals, while the groove walls which are of a diterent shape and size have been given new numbers.

lt will be seen that the closure body again has a circular central portion 23, an outer ilange 29, a shoulder 33, and an intermediate annular groove Sil which is tted with a sealing ring 3l. The walls forming the groove 3o consist of a straight inner-wall 65, and an outer shorter wall 66 which is joined to bottom wall o7 by a large radius rounded corner 68. ln this case, the initial depth of the groove is greater than that of the blank previously described, and as will be seen, the sealing ring 3l lits almost entirely within the groove with the void space within the latter greatly exceeding the Volume of the ring.

The forming apparatus shown in FIG. 9 has a fixed lower base plate 79 which supports a central circular die block 7l that has an upper portion shaped to seat against the closure body portion Z8. The block 71 is held in normally spaced relationship to plate 7d by spring 72. Surrounding block '7l in spaced relationship is an outer annular supporting ring 7d, which is also supported in normally spaced relationship to plate 76 by a plurality of springs 75. The upper portion of ring 74 lits around closure flange Z9 and is provided with an internal annular seat 76 which supports the closure body shoulder 33.

Between ring 71% and block '7l is an intermediate annular forming member or punch 7S, having a base portion seated on plate The punch 78 is adapted for sliding movement relative to the members 7l and 74, and as can be seen has a width such that it underlies both side walls 65 and do of the groove, as well as the bottom portion e7 and the radiused corner ed, while being initially spaced from Contact with the body. Extending through the base plate 7i? are a plurality of reciprocal pins or push rods 79 which bear against the base of punch 78 and can be used to raise the punch at the proper time as Will hereinafter be explained. Movement of rod 79 is accomplished by means ol pneumatic pistons (not shown). This pneumatic driving means provides a cushioning action to prevent over deformation of the groove Walls as will hereinafter be explained.

The upper portion of the die consists of a single, solid block 82 which is xedly supported on an upper reciprocable plunger 83. Block S2 is of cylindrical shape and of a size to just fit within flange 29 so as to seat against both the closure portions 28 and shoulder 33, as well as covering the groove 3d. Block 82 may have an annular luie-edge @il formed thereon to seat Within a corner formed by the juncture of body portion 2S and the inner groove wall 65 so as to rigidly support this corner. The portion of block 82 covering the open mouth of groove 30 is fiat and lies in the same plane as the portions of the block which seat on the body portions 28 and 33. Under some circumstances, the portion of block 82 covering the mouth of groove 30 may be formed with an eX- tended lip for the purpose of varying the void-volume relationship in the finished device, or to control the finished width of the groove.

Y When the die block 82 descends, it seats on the closure body, as is illustrated in FIG. 11, closing the mouth of the groove 3@ and conining the ring 31 therein. Further descent of die block 82 compresses the lower springs 72 and 75, clamping the closure body tightly between the block S2 and the lower block and rings 71 and 74. Block 82 continues to move downwardly until the bottom wall 67 of the groove seats on the top of punch 78, as is illustrated in FIG. 12. At this time, the void space within groove 30 exceeds the volume of ring 3i. due to the initial depth of the closure groove wall 65.

With the die parts in this relative position, punch 7S is moved upwardly by the pins 79 forcing the walis of the groove to deform. Because of the larger radiused corner 63, the outer Wall 66 of the groove is bent inwardly in a reverse bend, and at the same time, the depth of the groove is lessened. Since the ring Si is formed of incompressible material, it acts as a stop to limit the deformation of the groove walls when the condition shown in FIG. 13 has been reached. Because the means driving the punch 73 provides an air cushion, any overforming of the groove walls is prevented once the ring 31 completely fills the groove md no extrusion of the ring can occur.

It will be seen that the rounded lower corner 68 of the outer groove wall has been made more square, and that the outer wall 66 has been inclined upwardly and inwardly by the punching action. The deformation of the groove wall is, of course, stopped when the volume of ring 31 is substantially equal to the void space within groove 3i?. Thus the desired void-volume relationship is achieved regardless of the initial tolerance variations in the diameter of ring 31.

When the die block 32 is retracted, the ring 31 returns to its initial upwardly rounded shape, as is shown in FIG. 14, so as to project out of groove 3G for sealing engagement. The inclined outer wall 6% of the groove acts to confine ring 31 within the groove 3i) to prevent its accidental separation. It can also be seen at this point, that the finished closure is substantially identical to the form first described, although the groove walls have been worked in a different manner to achieve the desired void-volume relationship. While in the forms shown only one of the side groove walls has been inclined inwardly towards the top or mouth of the groove, it may be desirable to incline both of these groove walls inwardly. This can be accomplished by preforming the bottom of the groove walls with a large radiused corner on both sides, rather than on one side as in the examples shown.

Nhile we have thus described in some detail preferred and alternate apparatus and methods for manufacturing the sealing closure, it is to be understood that variations and modifications will be apparent to those skilled in the art. Therefore, we do not wish to limit the scope of the invention by the foregoing, except as it is defined in the appended claims.

We claim:

1. The method of forming a sealing device including a retaining member formed of a ductile metal and a resilient, deformable, and substantially incompressible packing element having at least a portion with an arcuate peripheral shape in assembly therewith, comprising the steps of: preforming in said retaining member a groove having a volume initially less than the volume of said packing element; placing said packing element in said groove with said arcuate portion projecting above the CTI mouth of said groove; placing said retaining member in a forming asesmbly with the walls of said groove disposed in a recess in said assembly; confining said packing element against the walls of said groove; and, with said element so confined, applying forming pressure directly to said element to deform it completely into said groove to volumetrically size said groove until the volume thereof is substantially equal to the volume of said packing element.

2. The method of forming a sealing device including a retaining member formed of a thin workable sheet material and a resilient, deformable, and substantially incompressible packing element held thereto, comprising the steps of: preforming in said retaining member a recessed groove having a volume different than the volume of said packing element; placing said element in said groove; placing said retaining member in a forming assembly with the walls of said groove disposed in a recess in said assembly; confining said packing element against the walls of said groove; and then, with said element so confined, applying forming pressure to said retaining member to shape the defining wall of said groove and to volumetrically size said groove so that its volume substantially equals the volume of said packing element.

3. The method defined by claim 2, in which the forming pressure is applied in a manner to constrict said groove adjacent its mouth and thereby frictionally hold said packing element therein.

4. The method defined by claim 2, in which the forming pressure is applied to said retaining member through said packing element.

5. The method of manufacturing a sealing closure including a retaining member formed of a ductile metal and a resilient, deformable, and substantially incompressible packing element having at least a portion with an arcuate peripheral shape in assembly therewith, comprising the steps of: preforming a continuous groove in said retaining member with opposite side walls and a bottom wall and with a volume greater than the volume of the packing element, the radius of curvature at the junction of said bottom wall and one of said side wallsV being substantially greater than the radius of curvature at the junction of said bottom wall with the other of said side walls; placing said packing element in said groove; placing said retaining member in a forming assembly with the Walls of said groove disposed in a recess in said assembly; and, with said element so confined, applying forming pressure to the retaining member to volumetrically size said groove until the volume thereof is substantially equal to the volume of said packing element and to constrict the mouth of said groove by bending said one of said sidewalls about the junction of the same with said bottom wall toward said other of said side walls.Y

6. The method of forming a sealing device comprising the steps of: forming a sheet metal retaining member with a recessed groove; forming a resilient, deformable, andsubstantiaily incompressible packing element into a configuration adapted for sealing deformation against an opposed surface, said element having a transverse different configuration than that of said groove; placing said element in 4said groove; placing said retaining member in a forming assembly with the walls of said groove disposed in a recess in said assembly; confining said element against the walls of said groove; and, with said element so confined, applying forming pressure to deform said element groove seated L1 said groove and having a volume substantially equal to the volume of said groove, the walls of said groove being shaped to deforrn said element from its free shape and rictionally retain it with its major portion Within said groove against the Walls thereof, said elernent having a portion normally projecting from said groove and adapted upon pressural engagement v. opposed part to be deformed into and conlne Within said groove to exert sealing pressure against said part.

8. A sealing device comprising: a retaining member forrned of a thin workable material and having a part engaging surface formed with a recessed groove therein, said groove having a relatively constricted opening adjacent its mouth; and a resilient, deformable, and substantially incompressible packing element seated in said groove and having a volume substantially equal to the volume of said groove, said element normally being substantially deformed from its free shape, with its major portion held Within said groove and substantialiy deformed against and frictionally 'neld by the walls of said groove, said element having a portion with a rounded surface normally projecting from said groove and being adapted upon pressural engagement with an opposed part to be deformed into and conned Within said groove and to exert ealing pressure against said part.

9. A sealing device for an open-mouthed container naving a sealing lip adjacent its mouth comprisin: a sheet metal cap having a iig-engaging surface with a recessed annular groove therein, said cap being adapted to be applied to said container to urge said surface into pressural engagement with said li and a resilient, deformable and substantially incompressible seaiing ring of a solid cross section throughout and a free shape different than tne shape of said groove, having a volume substantially equal to but no greater than the volume of said groove, the Walls of said groove being shaped to deorin said elenrent from its free shape and frictionally retain it with its major portion held against said Walis, and adapted to be coniined entirely therein, said ring having a portion normally projecting from said groove and adapted to be sealingly deformed against said lip and completely into said groove to deforrn said ring into uniform Contact with the Walls thereof ysubstantially coincidentally with the pressural engagement of said surface With said lip.

References Cited in the file of this patent UNITED STATES PATENTS 

8. A SEALING DEVICE COMPRISING: A RETAINING MEMBER FORMED OF A THIN WORKABLE MATERIAL AND HAVING A PART ENGAGING SURFACE FORMED WITH A RECESSED GROOVE THEREIN, SAID GROOVE HAVING A RELATIVELY CONSTRICTED OPENING ADJACENT ITS MOUTH; AND A RESILIENT, DEFORMABLE, AND SUBSTANTIALLY INCOMPRESSIBLE PACKING ELEMENT SEATED IN SAID GROOVE AND HAVING A VOLUME SUBSTANTIALLY EQUAL TO THE VOLUME OF SAID GROOVE, SAID ELEMENT NORMALLY BEING SUBSTANTIALLY DEFORMED FROM ITS FREE SHAPE, WITH ITS MAJOR PORTION HELD WITHIN SAID GROOVE AND SUBSTANTIALLY DEFORMED AGAINST AND FRICTIONALLY HELD BY THE WALLS OF SAID GROOVE, SAID 